Apparatus and Method for Handover Between a Heterogeneous Communication System and a Broadband Wireless Communication System

1. An operating method of a base station of a border cell of a broadband wireless communication system for a handover between the broadband wireless communication system and a target heterogeneous communication system, the method comprising: when a terminal enters the border cell of the broadband wireless communication system, sending, by the base station, a message, requesting to measure a signal level of a downlink, to the terminal using a modem for the broadband wireless communication system; when a signal level measured by the terminal falls below a preset threshold, requesting, by the base station, a handover to the target heterogeneous communication system over a core network; receiving, by the base station, a message, including channel allocation information for acquiring an UpLink (UL) channel of the target heterogeneous communication system, from the target heterogeneous communication system; and forwarding, by the base station, the message, including the channel allocation information, to the terminal using the modem for the broadband wireless communication system.

2. The operating method of claim 1 , wherein the channel allocation information is added to a ranging response (RNG_RSP) message.

3. An operating method of a terminal for a handover between a broadband wireless system and a target heterogeneous communication system, the method comprising: receiving, by the terminal using a first modem for the broadband wireless communication system, a message, requesting a measurement of a signal level of a downlink, from a base station of the broadband wireless system; sending, by the terminal using the first modem for the broadband wireless communication system, a message, reporting of the signal level of the downlink, to the base station; receiving, by the terminal using the first modem for the broadband wireless communication system, a message, including channel allocation information for acquiring an UpLink (UL) channel of the target heterogeneous communication system to the target heterogeneous communication system, from the base station; and attempting, by the terminal using a second modem for the target heterogeneous communication system, the handover to the target heterogeneous communication system using the channel allocation information received from the broadband wireless communication system.

4. The operating method of claim 3 , wherein the channel allocation information is received when the downlink signal level falls below a threshold after the terminal enters a border cell.

5. The operating method of claim 3 , wherein the attempting of the handover comprises acquiring an uplink resource and sending a handover complete report message.

6. An operating method of a base station of a border cell of a broadband wireless communication system for a handover between the broadband wireless communication system and a target heterogeneous communication system, the method comprising: when a terminal attempts a handover to a dummy cell of the broadband wireless communication system or when an active set of cells of the broadband wireless communication system includes only a border cell, requesting, by the base station, the handover to the target heterogeneous communication system; receiving, by the base station, a message, including channel allocation information for acquiring an UpLink (UL) channel of the target heterogeneous communication system, from the target heterogeneous communication system; and forwarding, by the base station, the message, including the channel allocation information, to the terminal using a modem for the broadband wireless communication system.

7. The operating method of claim 6 , further comprising: sending, by the base station, a handover response message relating to the dummy cell.

8. The operating method of claim 6 , further comprising: receiving, by the base station, a MOB_HO_ND message, informing of the handover to the dummy cell, from the terminal.

9. The operating method of claim 6 , wherein the channel allocation information is added to a ranging response (RNG_RSP) message.

10. An operating method of a terminal for a handover between a broadband wireless communication system and a target heterogeneous communication system, the method comprising: when a signal level of a downlink falls below a preset handover threshold, sending, by the terminal, a handover request to a base station of the broadband wireless communication system; after requesting the handover, receiving, by the terminal using a first modem for the broadband wireless communication system, a message, including channel allocation information for acquiring an UpLink (UL) channel of the target heterogeneous communication system to the target heterogeneous communication system, from the base station; and attempting, by the terminal using a second modem for the target heterogeneous communication system, the handover to the heterogeneous communication system using the channel allocation information received from the broadband wireless communication system.

11. The operating method of claim 10 , wherein the channel allocation information is received when the handover is performed to a dummy cell of the broadband wireless communication system.

12. The operating method of claim 10 , wherein the channel allocation information is received when an active set of the broadband wireless communication system includes only a border cell.

13. A base station of a border cell of a broadband wireless communication system for a handover between the broadband wireless communication system and a target heterogeneous communication system, the base station comprising: a controller for sending, to a terminal using a modem for the broadband wireless communication system, a message requesting a measurement of a signal level of a downlink, when the terminal enters the border cell of the broadband wireless communication system; a handover processor for requesting a handover to the target heterogeneous communication system over a core network, when a signal level measured by the terminal falls below a preset threshold; and an interface for receiving a message, including channel allocation information for acquiring an UpLink (UL) channel of the target heterogeneous communication system, from the target heterogeneous communication system, wherein the controller forwards the message, including the channel allocation information, to the terminal using the modem for the broadband wireless communication system.

14. The base station of claim 13 , wherein the channel allocation information is added to a ranging response (RNG_RSP) message.

15. A terminal for a handover between a broadband wireless communication system a target heterogeneous communication system, the terminal comprising: a controller for receiving a message requesting a measurement of a signal level of a downlink from a base station of the broadband wireless communication system and for sending a message reporting of the signal level of the downlink to the base station, based on a first modem for the broadband wireless communication system; and a handover controller for receiving a message including channel allocation information for acquiring an UpLink (UL) channel of the target heterogeneous communication system to the target heterogeneous communication system from the base station based on the first modem for the broadband wireless communication system, and for attempting the handover to the heterogeneous communication system using the channel allocation information received from the broadband wireless communication system based on a second modem for the target heterogeneous communication system.

16. The terminal of claim 15 , wherein the channel allocation information is received when a downlink signal level falls below a threshold after the terminal enters a border cell of the broadband wireless communication system.

17. The terminal of claim 15 , wherein the message generator acquires an uplink resource and sends a handover complete report message.

18. A base station of a border cell of a broadband wireless communication system for a handover between the broadband wireless communication system a target heterogeneous communication system, the base station comprising: a handover processor for requesting a handover to the target heterogeneous communication system, when a terminal attempts the handover to a dummy cell of the broadband wireless communication system or when an active set of the broadband wireless communication system includes only a border cell; and a controller for receiving a message including channel allocation information for acquiring an UpLink (UL) channel of the target heterogeneous communication system from the target heterogeneous communication system and for forwarding the message including the channel allocation information to the terminal using a modem for the broadband wireless communication system.

19. The base station of claim 18 , wherein the controller sends a handover response message relating to the dummy cell.

20. The base station of claim 18 , wherein the controller receives, a message MOB_HO_IND informing of the handover to the dummy cell, from the terminal.

21. The base station of claim 18 , wherein the channel allocation information is added to a ranging response (RNG_RSP) message.

22. A terminal for a handover between a broadband wireless system and a target heterogeneous communication system, the terminal comprising: a controller for sending a handover request to a base station of the broadband wireless communication system, when a signal level of a downlink falls below a preset handover threshold, based on a first modem for the broadband wireless communication system; and a handover controller for, after requesting the handover, receiving a message, including channel allocation information for acquiring an UpLink (UL) channel of the target heterogeneous communication system to the target heterogeneous communication system, based on the first modem for the broadband wireless communication system, from the base station and for attempting the handover to the heterogeneous communication system using the channel allocation information received from the broadband wireless communication system, based on a second modem for the target heterogeneous communication system.

23. The terminal of claim 22 , wherein the channel allocation information is received when the handover is performed to a dummy cell of the broadband wireless communication system.

24. The terminal of claim 22 , wherein the channel allocation information is received when an active set of the broadband wireless communication system includes only a border cell.